Knit-woven fabric and a machine for making the same

ABSTRACT

A machine for making a knit-woven twill fabric with double loops in wales between fabric stripes woven of warps and weft loops, has a system of oscillating lapping guides with eyelets for supplied weft threads ending in the wales, and cooperating with a system of latch needles which are reciprocated with the hooks moving on a curved endless path. The path of each needle hook is located below a section of the respective supplied weft thread. Each of the needles has an operating position located in an open warp shed, and the operating position is selected relative to the extreme position of the correlated oscillatory lapping guide so that the respective weft section passes over the open latch of the respective correlated knitting needle.

United States Patent [191 Zm atlik et al.

l l KNIT-WOVEN FABRIC AND A MACHINE FOR MAKING THE SAME [75] inventors: Josef Zrnatlik; Miloslav Jisa, both of Liberec; Josef Mohelnicky, Prague, all of Czechoslovakia [73] Assignee: Statni Vyzkuinny ustav Textilni,

Liberec, Czechoslovakia [22] Filed: Feb. 6, 1973 [21] Appl. No.: 330,044

[ Continuation-impart of Ser. No. 246,239, Apr. 21,

1972, Pat. No. 3,746,051.

[ 51 May 27, 1975 3,757,540 9/1973 Jackson 66/192 Primary ExaminerHenry S. Jaudon Attorney. Agent, or FirmMichael S. Striker [57] ABSTRACT A machine for making a knit-woven twill fabric with double loops in wales between fabric stripes woven of warps and weft loops, has a system of oscillating lapping guides with eyelets for supplied weft threads ending in the wales, and cooperating with a system of latch needles which are reciprocated with the hooks moving on a curved endless path. The path of each needle hook is located below a section of the respective supplied weft thread. Each of the needles has an operating position located in an open warp shed, and the operating position is selected relative to the extreme position of the correlated oscillatory lapping guide so that the respective weft section passes over the open latch of the respective correlated knitting needle.

1 Claim, 3 Drawing Figures sum-2m SHEET FIG. 2

KNIT-WOVEN FABRIC AND A MACHINE FOR MAKING THE SAME The present invention is a continuation in part application of our copending application Mohelnicky et al, Ser. No. 246,239, filed Apr. 2l, 1972, now US. Pat. No. 3,746,051. A related application entitled A Machine for Making a Knit-Woven Fabric, and the Fabric" is being filed under the name Mohelnicky et al by the same group of inventors.

BACKGROUND OF THE INVENTION The present invention relates to a knitwoven textile fabric comprising a warp knitted structure formed by weft loops, and stitch wales alternating with groups of warp threads interlaced with stitch-connecting loops to form a woven structure.

The term knit-woven fabric" is used in the present application to define partly woven and partly knitted hybrid fabrics made on a weaving machine or loom specifically modified for this purpose.

The present invention also relates to a weaving maching for making the knit-woven fabric of the general construction dislcosed in the copending US. Pat. application Ser. No. 246,239, which is designed for manufacturing a knit-woven fabric produced in a warp knitted cloth structure. An essential feature of such fabrics are stitch wales alternating with groups of warp threads interlaced with stitchconnecting loops in a woven structure.

When using the cloth warp knitted structure. the stitch wales form an open mesh stripe which does not substantially protrude from the fabric surface. Therefore, fabrics of this type are particularly suitable as materials for making air permeable garments, such as light summer shirtings and underwear material.

The weaving machine disclosed in the U.S. Pat. application Ser. No. 246,239, is provided with means for forming warp sheds of warp threads, and includes a knitting mechanism for forming a warp knitted structure of weft threads taken off from a stationary supply. Means are provided for beating up the stitchconnecting loops at the fell of the fabric.

The knitting mechanism comprises a system of oscillatory lapping guide elements adapted to penetrate, in the closed shed position, the warp sheet and in the open shed position, the warp threads of at least one shed plane. The lapping guide elements cooperate with a system of latch needles located across the fabric for engaging the lapped weft threads and to form stitch wales therefrom. The lapping arms of the lapping guide elements have free ends with a weft thread guiding eyelet, and are adapted to oscillate in an open shed from an intermediate starting position in which a perpendicular projection of the lapping arms onto the plane of a closed shed is parallel to the warp threads, to one of two extreme lapping positions and back again whereupon the lapping arms move into the next open shed to the same or opposite extreme lapping position, and back again.

The system of needles reciprocates from a starting position in front of the beat up plane to an operating position located in the open shed, and back again. The lapping guide elements are respectively registered with the knitting needles and are located directly opposite the knitting needles.

The motion of the knitting needles relative to a lapping guide element is timed so as to cause the knitting needles to start the movement into the shed prior to the start of the lapping guide elements from their intermediate starting position.

The path along which the hook of the needle moves from the foremost starting position to an operating po sition, extends above a weft thread section between a stitch wale formed by the adjacent knitting needle and the weft thread guiding eyelet of the lapping arm, so that the weft thread section is located below the needle shank in the region behind the open latch.

SUMMARY OF THE INVENTION It is an object of the present invention to broaden the range of knit-woven fabrics which can be produced on a weaving machine of the type disclosed in the U.S. Pat. application Ser. No. 246,239, without substantially affecting the performance of the machine.

The object can be attained in accordance with the invention by making a knit-woven fabric comprising a warp knitted structure formed by weft loops, and stitch wales alternating with groups of warp threads interlaced with stitch connecting loops to form a woven structure. In accordance with the invention, the warp knitted structure is a twill having double stitches in the wales.

A knit-woven fabric according to the invention can be described to have groups of warp threads interlaced with connecting weft loops to form woven stripes, and stitch wales alternating with the stripes, each stitch wale having a series of double stitches formed by weft loops so that the obtained warped knitted structure is a twill. Each double stitch includes a closed stitch and an open stitch formed by different weft loops.

A weaving machine for manufacturing the ahovedescribed knit-woven fabric is distinguished from the knitting machine of the prior art, inasmuch as the path of the knitting needle while moving from the foremost starting position to the operating position, is located below a weft thread section extending from the stitch wale formed by the adjacent knitting needle to the weft thread guiding eyelet of the lapping guide element. The relative position of the knitting needles in the operative position and that of the lapping guide element in the extreme lapping position, is selected so as to cause the weft thread section to pass over the open latch of the knitting needle.

By making the warp knitted structure a twill structure, it is assured that the connecting bight formed by the passage of one weft loop into the following weft loop formed by one weft thread, doubles the stitch in the wale. Due to this structure, the fabric is air permeable within the wale stripe areas, and the wales form over the fabric surface longitudinal projections favorably influencing the heat-insulating characteristics of the fabric, since if such fabric is placed on a smooth body surface, the projections define therewith and with the surface of the longitudinal stripes, a plurality of air filled pockets. Consequently, such a knit-woven fabric with a twill structure is particularly suitable for manufacturing underwear of polyamide materials since the stitch wales project from one side of the fabric, preventing direct adhering to the skin. The fabric is also suitable for manufacturing laminated outerwear,

Another important advantage of the fabric according to the invention is that the fabric is run-proof to a considerable extent, particularly if compared with knitwoven fabric having instead of the twill structure, an atlas or sateen warp knitted structure.

The weaving machine according to the U.S. Pat. application Ser. No. 246,239 can be easily adapted for manufacturing the fabric of the present invention. Substantially, it is only necessary to use knitting needles with particularly long latches projecting beyond the hooks. Also, the operating edge of the supporting bar over which the fabric is taken off, and which controls the knitting needles, has to be adjusted appropriately.

The novel features which are considered as characteristic for the invention are set forth in particular in the appended claimsv The invention itself, however, both as to its construction and its method of operation, together with additional objects and advantages thereof, will be best understood from the following description of specific embodiments when read in connection with the accompanying drawing.

BRIEF DESCRIPTION OF THE DRAWING FIGv l is a schematic view showing a fabric structure in accordance with the invention on an enlarged scale;

FIG. 2. is a partially schematic side view of the operating parts of a weaving machine for making a knitwoven fabric; and

FIG. 3 is a fragmentary perspective view illustrating the operating parts of the machine.

DESCRIPTION OF THE PREFERRED EMBODIMENT Referring now to the drawings, and particularly to FIG. 1, which illustrates a preferred embodiment of a knit-woven fabric, it can be seen that a system of weft threads 1 form a warp knitted structure comprising double stitches 2 and 3 in each wale 4. Stitches 2 are closed, and stitches 3 are open. The closed stitches 2 of each pair of stitches 2, 3 are formed by the end bights of hairpin-shaped weft loops 5. Pairs of connecting loops 6 of the stitches 2 disposed side by side or end to end across the fabric, constitute a sectional or loop weft 7 which is located between the wales 4 of the stitches 2 interlaced to form a plain weave with warp threads 8. Knitted structure comprising wales 4 of double stitches 2 and 3. The wales 4 consist of closed reverse stitches 2 doubled by open not reverse stitches 3. The closed reverse stitches 2 are formed by end bights of hairpin shaped loops 5. Pairs of stitch connecting loops 6 of the closed reverse stitches 2 and of the open not reverse stitches 3, which stitch connecting loops 6 are disposed side by side or end to end across the fabric, constitute a sectional or loop weft 7. Between the wales 4 there are located longitudinal woven stripes 9 formed by warp threads 8 interlaced with said stitch connecting loops 6 of the closed reverse stitches 2 and of the open not reverse stitches 3 to form a plain weave. Each weft thread 1 forms in one wale 4 one closed re verse stitch 2 and in the adjacent wale 4, one open not reversed stitch 3.

The open not reverse stitch 3 actually assumes the function of a connecting link between the successive hairpin-shaped loops formed by one and the same thread 1.

For the sake of clarity, the stitches 2 and 3 in each wale 4 are shown by lines of different thickness.

The width of the pair of hairpin-shaped loops 5 formed by one and the same weft threads 1 is indicated by a bracket carrying the reference numeral 9'. As apparent from FIG. 1, the pairs of hairpin-shaped loops 5 formed by one and the same weft thread. overlap each other,

The fabric has a selvedge shown at the left side of FIG. 1, the opposite right selvedge, not shown, being a mirror image of the left selvedge. The outer stitches of the marginal longitudinal woven stripe 9, which are not interlaced to form a wale and which lie on the level of the sectional or loop weft 7, are indicated as loops 2'. A characteristic feature of the fabric according to the invention resides in the fact that the connecting bight between the two successive hairpin-shaped loops 5 formed by one and the same weft thread 1, forms open not reverse stitches 3, doubling the closed reverse stitches 2 in the wale 4.

FIGS. 2 and 3 schematically show a weaving machine for manufacturing the fabric according to the invention shown in FIG. 1. As best shown in the drawing, and particularly in FIG. 2, the reference numeral 10 denotes a cross bar fixedly attached between side walls, not shown, of the weaving machine below the sheet of warp threads 5. Cross bar 10 oscillatably supports lapping guide element 13 arranged side by side upstream of the heald shafts 11 and 12.

Each lapping guide element 13 has a stem provided, on its intermediate portion, with a lapping arm or projection 15 which terminates in a guiding eyelet 16 into which a weft thread 1 is threaded, which is taken from a stationary supply package, not shown.

Simultaneous oscillating movement of the lapping guide elements 13 is derived from a rack 17 which is reciprocated by drive means, not shown.

The machine further comprises a sley 18 carrying a reed 19. Within each open shed, when the sley 18 is its rearmost dwell position, the lapping guide elements 13 are simultaneously moved from an intermediate starting position into one of two extreme lapping positions and back again, and in the following open shed interval, the lapping guide elements are moved again from the intermediate starting position into the opposite extreme lapping position and back again.

Opposite each lapping guide element 13, a knitting latch needle 20 is located, whose longitudinal axis points, in the intermediate starting position of the lapping guide element 13, toward the eyelet 16 of the lapping guide element 13.

The shanks 30 of the knitting needles 20 are fixed in a movable needle bed 21 provided with a sleeve 22 surrounding an eccentric circular cam 23 mounted on a shaft 24 which is driven in a transmission ratio of 1:] from the crank shaft, not shown, of the machine.

The hooks 25 of the knitting needles 20 follow, during operation, an endless closed curvilinear path 26 from the formost starting position in the direction of the arrow 27 to a retracted operating position while the crank shaft of the machine performs a single revolution. The direction of rotation of the eccentric cam 23 is indicated by the arrow 28. The latch 29 of each knitting needle 20 is slightly longer than conventional needle latches.

The shanks 30 of the knitting needles 20 are guided by an operating edge 31 of a supporting bar 32 during movement from the foremost starting positions to the retracted operating positions. Supporting bar 32 is adjustable in vertical direction in a conventional manner.

Warp threads 8 pass between the dents of the reed l9, and there are provided wider spaces. not shown. for the passage of lapping guide elements and knitting needles 20. In the intermediate starting position of the lapping guide elements 13, the eyelets 16 point toward the apex of the shed being formedv The produced fabric T. controlled by the operating edge 31 of the supporting bar 32, is taken off over a breast beam by a take up device, not shown.

The movement of the knitting needles is phase shifted so that they enter the shed prior to the start of the lapping guide elements 13 from the intermediate starting position,

The supporting bar 32 is vertically adjustable. and controls by the operating edge 31. the knitting needles 20 while the knitting needles move from the foremost starting position into the open shed below the weft threads 1 which extend from the fell of the fabric T to the guiding eyelets 16 of the lapping guide elements 13.

The weaving machine, partially shown in FIGS. 2 and 3, operates as follows:

When the sley 18 is moved from the front dead center position shown in broken lines to rear dead center position shown in solid lines, the hooks of knitting needles 20 located in front of the beat up plane of the fabric T. pass through the spaces between the dents of the reed l9 and enter the opening shed, simultaneously distributing the warp threads 8 into corresponding positions in the respective longitudinal stripes 9. As soon as sley 18 has reached its rear dead center position or dwell position, the lapping guide elements 13 swing from their intermediate starting position into one of the extreme lapping positions, for example to the left hand position.

The knitting needles 20 are controlled by the operating edge 31 in such a manner that the path of their movement is located below the sections of weft threads 1 which extend from the wales 4 to the guiding eyelets 16 of the lapping guide elements 13. Before the lapping guide elements 13 have ended their movement. the knitting needles 20 enter from below into their operat ing positions, and place their open hooks 25 under the taut weft threads 1 which extend from the fabric T being made, in the region of the wales 4, above the shanks of the knitting needles 20, and also above the opened latch 29. In this manner. the weft threads 1 form the first parallel legs of the stitch connecting loops 6, see also FIG. 1. While the sley 18 is still in the dwell position, the lapping guide elements 30 return to the intermediate starting positions whereby the second legs of the stitch connecting loops are formed.

Simultaneously with the movement of the sley 18 from their rear dead center position to the beat-up position, the knitting needles 20 return back to the starting positions, together with the stitches of weft thread 1, caught in the hooks 25, and place the first legs of the stitch-connecting loops 6 on the level of the beat-up plane of the fabric T. After turning of the lapping guide elements 13 to the intermediate starting position, the reed 19 heats up the simultaneously formed second legs of the stitch connecting loops 6 into the fell of the fabric T, during a simultaneous shed change.

Due to the path of the knitting needles 20 moving from its foremost position to the operating position. weft thread 1, in the section between the wale 4 and the eyelet 16 of lapping element 13, passes over the open latch 29 of the needles 20 located in the region of this wale 4. During the return movement of the needles 20, the same thread is displaced in the form of a stitch 3 into the hook 25 due to the closing movement of the needle latch 29, and is added to the new stitch 2 formed by the lapping guide element 13. When the knitting needles 20 finish their movements. the old stitches 2, 3 are drawn over the new stitches 2, 3 and the wale 4 is formed.

During the next shed interval, the above-described cycle is repeated. except that the lapping guide elements [3 are moved to the opposite extreme position,

it is apparent from FIG. 3 that the weft threads extend from the respective wale 4 to the guiding eyelets 16 of the lapping guide elements 13 over the opened latch 29 of the knitting needles 20 which is located in the region of the wale 4. For the sake of clarity. weft threads I in the region of wale 4 are drawn in heavier lines.

In the preferred embodiment of the fabric according to the invention, the stitch connecting loops are inter laced with warp threads in a plain weave The stitch connecting loops. however. may interlace the warp threads in an other weave than the plain weave, such as, sateen, twill. or any dobby or Jacquard weaves.

The number of warp threads between two adjacent wales is to be selected in accordance with that fabric s structure.

It will be understood that each of the elements described above, or two or more together. may also find a useful application in other types of machines for making a knit-woven fabric differing from the type described above,

While the invention has been illustrated and described as embodied in a warp knitted twill structure and a machine for making the fabric, it is not intended to be limited to the details shown, since various modifi cations and structural changes may be made without departing in any way from the spirit of the present in vention,

Without further analysis, the foregoing will so fully reveal the gist of the present invention that others can by applying current knowledge readily adapt it for various applications without omitting features that. from the standpoint of prior art, fairly constitute essential characteristics of the generic or specific aspects of this invention and, therefore, such adaptations should and are intended to be comprehended within the meaning and range of equivalence of the following claims.

What is claimed as new and desired to be protected by Letters Patent is set forth in the appended claims.

We claim:

1. A knit-woven fabric, comprising a warp-knitted structure having wales of double stitches spaced across the width of the fabric formed by weft threads and consisting of closed reverse stitches doubled by open not reverse stitches, and longitudinal woven stripes located between said wales and formed by warp threads interlaced with double weft threads composed of connecting loops of closed reverse stitches and of connecting loops of open not reverse stitches, each pair of said weft threads forming in one wale one closed reverse stitch and in an adjacent wale one open not reverse stitch. 

1. A knit-woven fabric, comprising a warp-knitted structure having wales of double stitches spaced across the width of the fabric formed by weft threads and consisting of closed reverse stitches doubled by open not reverse stitches, and longitudinal woven stripes located between said wales and formed by warp threads interlaced with double weft threads composed of connecting loops of closed reverse stitches and of connecting loops of open not reverse stitches, each pair of said weft threads forming in one wale one closed reverse stitch and in an adjacent wale one open not reverse stitch. 